(a) Field of the Invention
The present invention relates to a plasma display panel (hereinafter, PDP), and more particularly, to a surface discharge type PDP with a electrode structure in which a pair of discharge sustain electrodes formed on one substrate and have a corresponding pair of bus electrodes within each discharge cell between two substrates to cause a display discharge.
(b) Description of the Related Art
Generally, a plasma display panel is a display device in which ultraviolet rays generated by gas discharge excite phosphors to realize predetermined images. Such a plasma display panel is popular for wide screen display devices since it enables the manufacture of large screen sizes with high resolution.
Referring to FIG. 4, a generally known PDP is formed with address electrodes 112 along one direction (in the X-axis direction of the drawing) on a rear substrate 110, and a dielectric layer 113 is formed on a surface of the rear substrate 110 covering the address electrodes 112. On the dielectric layer 113, barrier ribs 115 of stripe pattern are formed to place between each of the address electrodes 112, and red (R) , green (G), and blue (B) phosphor layers 117 are formed on each of the barrier ribs 115.
In addition, discharge sustain electrodes 102, 103 having a pair of transparent electrodes 102a, 103a and bus electrodes 102b, 103b are formed along the direction crossing the address electrodes 112 (in the Y-axis direction of the drawing) on a surface of a front substrate 100 opposing the rear substrate 110. A transparent dielectric layer 106 and a MgO protection film 108 are formed covering the discharge sustain electrodes on a surface of the front substrate 100.
The region where the address electrodes 112 on the rear substrate 110 are intersected with the discharge sustain electrodes 102, 103 on the front substrate 100 is to be a portion where discharge cells are formed.
An address voltage Va is applied between the address electrodes 112 and the discharge sustain electrodes 102, 103 to cause address discharge, and a sustain voltage Vs is applied to a pair of the discharge sustain electrodes 102, 103 to cause sustain discharge. Then, the generated vacuum ultraviolet rays excite phosphors so that they emit visible light through the front substrate 100 and thereby display PDP images.
However, the PDP having the discharge electrodes 102, 103 and the barrier ribs 115 in a stripe formation as shown in FIG. 4, may cause crosstalk between the discharge cells adjacent with the barrier ribs 115. In addition, it may cause the misdischarge between the adjacent discharge cells since the discharge areas are connected to one another along the direction where the barrier ribs 115 are formed. In order to prevent these problems, the distance between the discharge sustain electrodes 102, 103 corresponding to the adjacent pixels needs to be over a certain level, which reduces improvements in efficiency.
To solve the above problems, PDPs having improved electrodes and barrier ribs as shown in FIGS. 5 have been suggested. The PDP has a configuration such that transparent electrodes 123a of discharge sustain electrodes 123 are extended from bus electrodes 123b to face each other in a pair within each of the discharge cells. For the purpose of reducing the crosstalk between the adjacent discharge cells and enhancing the emission efficiency by increasing the phosphor coated area, a PDP is suggested which has barrier ribs 125 of the matrix type formed with vertical barrier ribs 125a and horizontal barrier ribs 125b perpendicular to each other. Japanese Patent Laid-open No. 1998-149771 describes such a plasma display panel.
The PDP having the above structure operates such that the emission of the plasma discharge starts in the sustain area between a pair of opposing discharge electrodes, and diffuses around the edge until it becomes extinct. Accordingly, the characteristics of the shape of the members forming the discharge cells have a significant influence on the sustain discharge. In particular, the shape of the discharge sustain electrodes 123 causing the sustain discharge and the barrier ribs 125 that define the shape of the discharge cells greatly influence the sustain discharge.
However, the shape of the discharge sustain electrodes 123 mentioned above causes the strong initial discharge partially in the discharge gap, and if the initial discharge occurs partially, the plasma discharge cannot be efficiently diffused within the discharge cells, and thereby the discharge efficiency deteriorates.